Quick-recharging valve.



J. R. SNYDER. QUICK REGHARGING VALVE. APPLICATION FILED AUG. 27, 1912.

Patented Apr. 28, 1914.

INVEN WITNESSES coLUM UNITED STATES PATENT OFFICE.

JACOB RUSH SNYDER, 0F PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO PERCY E.DONNER, OF PITTSBURGH, PENNSYLVANIA.

QUIGK-REGHARGING- VALVE.

Specification of Letters Patent.

Patented Apr. 28, 1914.

Application filed August 27, 1912. Serial No. 717,367.

To (ZZZ whom it may concern Be it known that I, Jnoon RUsri SNYDER, aresident of Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement inQuick-Recharging Valves, of which the following is a specification.

This invention relates torailway air brakes, and its purpose is toprovide for quickly recharging the auxiliary reservoir in such mannerthat the triple valve will not fail to go to full release position, andalso to enable the partial recharging of the auxiliary reservoirswithout releasing the brakes.

Gene 'ally stated the invention comprises a valve device so arranged asto admit fluid pressure from the train pipe to the auxiliary reservoiruntil the latter is charged to a point somewhat less than the point ofequalization with the train pipe, whereupon such recharging connectionis broken and the completion of the recharging of the auxiliaryreservoir thereafter takes place through the usualv feed groove in thetriple valve, thereby insuring the triple valve being moved to fullrelease position.

The accompanying drawing represents a sectional view through the specialrecharging valve and shows diagrammatically the cooperating parts of theair brake system.

In the drawings 1 represents the usual train pipe having a connection 2to the triple valve 3. 4: is the auxiliary reservoir and 5 the brakecylinder. These parts are represented merely diagrammatically, and inminiature.

The recharging valve is connected between the train pipe and theauxiliary reservoir, and comprises a casing formed in three parts orsections, 7, 8 and 9, suitably secured together. In this casing is acontrol. valve and suitable differential piston mechanism for actuatingthe same. The differential piston mechanism is shown as formed of twodiaphragms, to-wit: a large diaphragm 10 clamped between the casingsections 8 and 9, and a small diaphragm 11 clamped between the casingsections 7 and 8. The space 12 between the diaphragms is open to theatmosphere through port 13 so that no pressure can exist between thediaphragms.

he large diaphragm 10 is subject to pressure in chamber 30 in the casingsection 9, which chamber is connected to the auxiliary reservoir by pipe14, and the smaller diaphragm 11 is subject to pressure in chamber 15 1ncasing section 7 which is connected to the train pipe 1. The diaphragms10 and 11 are connected by a stem 16 so that they must move in unison,and which stem preferably is hollow, being provided with the passage 17connecting with cross port 18 opening into chamber 15, said passage andcross port forming the direct connection between the train pipe andauxiliary reservoir. The lower part of the stem 16 is surrounded by ahelical spring 19 interposed between the small diaphragm 11 and a crossweb or spider 20 in casing section 15. The lower end of stem 16 carriesthe regulating valve 21, shown in the form of a check valve cooperatingwith seat 22 in the lower head 23 of the casing section 7, andcontrolling the train pipe port 2 1. The valve 21 may be secured to thestem 16 so as to be lifted positively thereby, but preferably has a lostmotion connection thereto, such as by the projection 25 on the stem 16loosely entering the tubular portion 26 of the valve.

The operation of the valve is as follows: To will assume that the triplevalve is in application position and the auxiliary reservoir partly orwholly depleted, and it is desired to recharge said reservoir. Theadmission of pressure fluid to the train pipe lifts valve 21 and the airenters chamber 15 and thence passes by cross port 18 and passage 17 inthe stem 16 to chamber 13 and thence through the connection 14 to theauxiliary reservoir. The diaphragms 10 and 11 are normally in theposition shown in the drawing, and will remain in such position untilthe pressure in the auxiliary reservoir acting in chamber 30 against thelarge dia phragm 10 overbalances the pressure in chamber 15, plus thetension of spring 19, acting against the small diaphragm 11. The

l diaphragms are so proportioned in area and the spring 19 is of suchstrength that this overbalancing of pressure on the diaphragm 10 occursprior to equalization of auxiliary reservoir pressure with trainpipepressure,

and when it occurs it forces the differential piston mechanismdownwardly, seating valve 21 and stopping the flow of air from the trainpipe to the auxiliary reservoir through this direct connection. Thedifl'erential piston mechanism and spring can be proportioned to shutoff the direct flow of l air from the train pipe to the auxiliary reser-Cir voir at any point short of equalization with train pipe pressure.For instance, if the auxiliary reservoir is to be charged to 9O pounds,this valve can be so arranged as to cut off the flow of airtherethrough, say at or pounds, as experience may show to be goodpractice. At this stage the pressure in the auxiliary reservoir is stillconsiderably below maximum train pipe pressure so that as soon as valve21 closes the full train pipe pressure acts against the outer face ofthe main piston of the triple valve, and as the inner face of said mainpiston is subject to the lesser pressure in the auxiliary reservoir, thetriple valve is forced to move to full release position, and thecompletion of the charging of the auxiliary reservoir takes placethrough the usual feeding groove until the auxiliary reservoir pressureequalizes with the train pipe. \Vhile, therefore, providing for thequick recharging of the auxiliary reservoir, this valve is soconstructed as to stop such direct charging at some point less thanequalization with train pipe pressure, thereby insuring a sufficientpreponderance of the train pipe pressure over that directly charged intothe auxiliary reservoir as to force the triple valve to full releaseposition. This valve can also be utilized for recharging the auxiliaryreservoir when the triple valve is in service application position andwithout releasing the brakes, by merely admitting the air sufficientlyslowly into the train pipe so that it will be taken care of by thepassage through the recharging valve and therefore will not force thetriple valve to release position. This enables the auxiliary reservoirsto be recharged to the predetermined amount less than full equalizationto which the recharging valve is adjusted, and enables the brakes to beheld applied while partially replenishing the auxiliary reservoirs, suchas is desirable when coming down long grades. If it is desired to fullyrecharge the auxiliary reservoir when coming down long grades, thetriple valves, may, of course, be moved to full release position, butthey need not remain long in that position because the auxiliaryreservoirs have been already recharged fairly close to their capacity,and consequently, the brakes need remain released for such a short timethat the train would not get beyond control.

As the auxiliary reservoir has been practically recharged while thebrakes remain applied, the engineer is able to further increase thepressure in the brake cylinders even though he had previously made afull service application, which additional application may be verydesirable due to the brake cylinder pressure leaking oft, or it may benecessary to secure a higher braking power in the brake cylinders tostop a train of loaded i cars than one of empty cars, as the brakingpower for freight cars is based upon some predetermined percentage ofthe light or empty weight and not the loaded weight. Therefore a fullservice application might not produce the desired result on a train ofloaded cars. Consequently it is a convenience to be able to recharge theauxiliary reservoirs without having to release the pressure in the brakecylinders, and then further build up the brake cylinder pressure.

The recharging valve described obviously can be used with any form oftriple valve and in any automatic air brake system, and can be appliedto any existing air brake equipment by merely connecting the samebetween the auxiliary reservoir and the train pipe.

Any form of differential piston mecha nism may be used in lieu of thetwo diaphragms illustrated, and various forms and arrangements of valvesand of bypass connection between the valve and the auxiliary reservoir,will readily suggest themselves to those skilled in the art.

What I claim is:

1. In a fluid pressure brake, the combination with a train pipe, triplevalve, auxiliary reservoir and brake cylinder, of a recharging Valvedevice interposed between the train pipe and auxiliary reservoir andincluding a movable abutment subject on one side to auxiliary reservoirpressure and on its opposite side to train pipe pressure, a valveoperatively connected to said abutment and arranged to controlcommunication between the train pipe and the auxiliary reservoir andalso controlling communication between the train pipe and the one sideof said movable abutment, and a. spring acting in conjunction with thepressure on the train pipe side of said movable abutment.

2. In a fluid pressure brake, the combination with a train pipe, triplevalve, auxiliary reservoir and brake cylinder, of a recharging valvedevice interposed between the train pipe and auxiliary reservoir andincluding differential piston mechanism having its small area subject totrain pipe pressure and its large area subject to auxiliary reservoirpressure and arranged to maintain communication from the train pipe tothe auxiliar reservoir until the auxiliary reservoir pressure reaches apredetermined point short of equalization with the train pipe and tothen close said connection, whereby the equalization of the auxiliaryreservoir with the train pipe is completed through the triple valve.

3. In a fluid pressure brake, the combination with a train pipe, triplevalve, auxiliary reservoir and brake cylinder, of a recharging valvedevice interposed between the train pipe and auxiliary reservoir andinclud ing differential piston mechanism having its small area subjectto train pipe pressure and its large area subject to auxiliary reservoirpressure and arranged to maintain communication from the train pipe tothe auxiliary reservoir until the auxiliary reservoir pressure reaches apredetermined point short of equalization with the train pipe and tothen close said connection, whereby the equalization of the auxiliaryreservoir with the train pipe is completed through the triple valve, anda spring acting in conjunction with the pressure on the smaller area ofsaid differential piston.

4. In a fluid pressure brake, the combination with a train pipe, triplevalve, auxiliary reservoir and brake cylinder, of a rechargone end tothe auxiliary reservoir and at its opposite end to the train pipe, aconnection through said valve from the train pipe connection to theauxiliary reservoir connection, a differential piston in said casingsubject on its larger area to auxiliary reservoir pressure and on itssmaller area to train pipe pressure, and a valve operatively connectedto said dilierential piston and controlling communication between thetrain pipe and the auxiliary reservoir and also controllingcommunication between the train pipe and the smaller area of saiddifferential piston.

5. In a fluid pressure brake, the combination with a train pipe, triplevalve, auxiliary reservoir and brake cylinder, of a recharging valvecomprising a casing connected at one end to the auxiliary reservoir andat its opposite end to the train pipe, a coning valve comprising acasing connected at nection in said valve from the train pipe connectionto the auxiliary reservoir connection, a valve controlling saidconnection, a differential piston in said casing subjected on its largerarea to auxiliary reservoir pressure and on its smaller area to trainpipe pressure and operatively connected to said valve, and a springcooperating with the pressure acting on the smaller area of saiddifferential piston.

6. In a fluid pressure brake, the combination with a train pipe, triplevalve, auxiliary reservoir and brake cylinder, of a recharging valvecomprising a casing connected at one end to the auxiliary reservoir andat its opposite end to the train pipe, a connection through said valvefrom the train pipe connection to the auxiliary reservoir connection, adifferential piston in said casing subject on its larger area toauxiliary reservoir pressure and on its smaller area to train pipepressure, a valve operatively connected to said differential piston andcontrolling communication between the train pipe and the auxiliaryreservoir and also controlling communication between the train pipe andthe smaller area of said dilierential piston, and a spring acting inconjunction with the pressure on the smaller area of said differentialpiston.

In testimony whereof I have hereunto set my hand.

JACOB RUSH SNYDER. lVitnesses 11. P. LARKIN, MARY E. GAHooN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. 0.

